Birth Control and HIV

Hormonal Birth Control and HIV AIDS

One of the standard warnings given to women who choose to use hormonal birth control methods such as the birth control pill is that while these contraceptives may help prevent pregnancy, they do not provide protection against sexually transmitted diseases (STDs) such as HIV/AIDS. Recent studies have suggested that the risk of HIV transmission among women using hormonal birth control methods is actually increased. Furthermore, the reasons behind this increased risk of HIV/AIDS transmission among women using birth control goes beyond the fact that hormonal contraception does not provide STD protection. So how does hormonal birth control increase the risk of HIV/AIDS?

HIV AIDS Transmission

In order for the HIV virus to be transmitted, there must be a point of access within the body where the infection may take place such as an open sore, a needle prick, a bleeding surface, inflammation or an otherwise fragile surface. Some studies suggest that the side effects associated with sex hormones that are used in hormonal birth control methods may increase the likelihood of these types of infection sites to occur.

Types of Hormonal Contraceptives

A report published by the International AIDS Society has linked the use of an injectable contraceptive known as depot medroxyprogesterone acetate (DMPA) with an increased risk of HIV-1 infections. Interestingly, women using DMPA were at a greater risk of HIV infection than women using no form of contraception at all.

In addition, the same study suggested that there may be a link between HIV infection and oral contraceptives or birth control pills.

Birth Control Pills and HIV

The hormones that are used in birth control pills can produce a variety of effects on the female reproductive system. Some explanations as to how this hormonal birth control method may increase the risk of HIV/AIDS transmission include the following.

Irregular Bleeding
All types of hormonal birth control methods cause irregular uterine bleeding and produce common birth control symptoms such as "spotting" or "breakthrough bleeding." Breakthrough bleeding is typically caused by an excessive thickening of the lining of the uterus (endometrium).

The effects of hormonal birth control on the endometrium make it an ideal site of infection, since the uterine lining becomes a large, bleeding surface where HIV transmission may take place. In addition, the presence of blood in the vagina may change the pH in the area, and make it more susceptible to HIV and STD infections.

The presence of blood in the vagina also increases bidirectional HIV transmission (i.e. from men to women and vice versa). This is because the HIV virus is found in highest concentrations in the blood.

Cervical Ectopy
Hormonal birth control causes cervical ectopy - a condition in which a layer of endo-cervical cells extends beyond the opening of the cervix. This fragile layer of cells replaces a thick membrane that is comprised of multiple layers and is resistant to microorganisms or STDs.

The increased surface area of this fragile layer (known as the cervical endothelium) becomes an ideal site for HIV and STD infection. This is because the cervical endothelium is the site of the chemokine receptors CCR-5 and CXCR-4, which must be present in order for HIV infection to occur. In fact, the cervix is considered to be the main site of HIV infection in women.

Progesterone Hormones
Progesterone hormones used in birth control pills can have several effects on the body that may increase the risk of HIV infection. The side effects of progesterone hormones may include the following:

• immune system suppression
• thinning of the endometrium
• endometrium atrophy
• irregular uterine bleeding

All of these factors may increase the risk of HIV transmission.

Other Considerations
Another common symptom of the birth control pill experienced by women is vaginal dryness. Vaginal dryness can lead to abrasions of the tissue surface, which can create an ideal site of HIV infection.

Lastly, it is important for all women who may be at risk of HIV infection or are using hormonal contraceptives to use barrier methods such as condoms that offer protection from STDs such as HIV/AIDS.